Understanding your period
What a period is, how long a normal cycle lasts, and what you can use during your period.
✓ Clinically reviewed · Catherine, RN & Juah, RN
📝 Audio transcript
Understanding your period.
A period is the part of the monthly cycle when blood comes out of the vagina for a few days. It is a normal part of a healthy body.
Most periods come about every 28 days, but anywhere from every 21 to 35 days is common. Bleeding usually lasts 2 to 7 days, often about 5, and is heaviest in the first 2 days. The blood is red on heavy days and can be pink or brown on lighter days.
Periods usually start around age 12, but starting earlier or later is common and not usually a worry. For most girls, periods become regular by about age 16 to 18.
Before a period some people feel bloated, have sore breasts, mood changes, spots or headaches. This usually gets better when the period starts. Not everyone gets these feelings.
You can use pads (including washable, reusable pads), tampons, menstrual cups or period underwear. A tampon that is put in correctly should not be felt, and it cannot get lost inside the body.
When should I get help?
- Bleeding between periods, after sex, or after your periods have stopped for good (menopause).
- Missing three periods in a row when you are not pregnant.
- Any big change in your periods that worries you.
Key things to remember
- A cycle of 21 to 35 days is common.
- Bleeding for 2 to 7 days is common.
- Periods often start around age 12 and become regular by 16 to 18.
📖 Read the full lesson
A period is the part of the monthly cycle when blood comes out of the vagina for a few days. It is a normal part of a healthy body.
Most periods come about every 28 days, but anywhere from every 21 to 35 days is common. Bleeding usually lasts 2 to 7 days, often about 5, and is heaviest in the first 2 days. The blood is red on heavy days and can be pink or brown on lighter days.
Periods usually start around age 12, but starting earlier or later is common and not usually a worry. For most girls, periods become regular by about age 16 to 18.
Before a period some people feel bloated, have sore breasts, mood changes, spots or headaches. This usually gets better when the period starts. Not everyone gets these feelings.
You can use pads (including washable, reusable pads), tampons, menstrual cups or period underwear. A tampon that is put in correctly should not be felt, and it cannot get lost inside the body.
📚 Sources
- NHS (UK) — Periods Last reviewed 5 Jan 2023 (review overdue) · accessed 31 Oct 2026
Written in plain language from these sources. It does not imply endorsement by these organizations.
HH-ART-001 · Version 1.0 · Last updated 4 Nov 2026
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